Firefox 121 end of life (EOL) date and support status
End of life End of life since 2024-01-23 (989 days ago)
Upgrade: Firefox 121 no longer receives fixes. Supported cycles: 157, 153, 115.
| Product | Firefox |
|---|---|
| Version cycle | 121 |
| Status | End of life |
| Released | 2023-12-19 |
| Active support until | — |
| End of life | 2024-01-23 |
| Latest version | 121.0.1 (2024-01-09) |
| Last verified | 2026-10-08 |
All Firefox versions → · Source: endoflife.date
Frequently asked questions
Is Firefox 121 end of life?
Yes. End of life since 2024-01-23 (989 days ago). It no longer receives security or bug fixes.
When does Firefox 121 reach end of life?
Firefox 121 reached end of life on 2024-01-23.
When was Firefox 121 released?
Firefox 121 was first released on 2023-12-19.
What is the latest Firefox 121 version?
The latest 121 release is 121.0.1, published on 2024-01-09.
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